Writing instrument



Jan. 27, 1959 w. H. KERSTEN WRITING INSTRUMENT 2 Sheets-Sheet 1 Filed July 5, 1955 i INVENTOR. 11/651432 ffjfensz'efl Z44 Mvas nited States .atent O WRITING INSTRUMENT William H. Kersten, Janesville, Wis., assignor to The Parker Pen Company, Janesville, Wis., a corporation of Wisconsin Application July 5, 1955, Serial No. 519,727

Claims. (Cl. 12042.03)

The present invention relates to writing instruments and more particularly retractable writing instruments.

A writing instrument of the general character noted includes a barrel or holder and a writing unit in the barrel having a writing point, movable between a retracted position in which the writing point is concealed in the barrel, and a projected position in which the writing unit is exposed forwardly beyond the barrel in a writing position.

An object of the invention is to provide a writing instrument of the foregoing general character having a writing unit movable to projected position by inertia, and having novel means for retaining the writing unit in projected position and for releasing it from such position for permitting its retraction by means contained in the instrument for that purpose.

Another object is to provide a writing instrument of novel construction in which the writing unit is releasably held in projected position by engagement with a fixed stop and is thus positively and non-yieldingly held against retraction by the forces imposed on the unit in writing,

A further object is to provide a writing instrument of the character noted in which the writing unit is positively and non-yieldingly held against retraction by fixed stop means wherein the writing unit is releasably retained in position engaging the stop means by yieldable. spring means, and magnetic means is'provided for retracting the unit.

Another object is to provide a retractable writing instrument of the general character noted having interengageable magnetic elements for retaining the writing unit in retracted position, in which the interengaging faces of the magnetic elements are specially shaped to provide greater area and consequent greater attractive forces.

A still further object is to provide a writing instrument of the foregoing character wherein release of the writing unit from the stop means is efiected, in one form of the invention, by merely tapping the instrument on a solid surface, and in another embodiment, by a hand manipulation such as flexing the pocket clip.

Other objects and advantages of the invention will appear from the following detailed description taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a longitudinal sectional view through a writing instrument embodying the principles of the invention, showing the writing unit in projected position;

Fig. 2 is a view similar to Fig. l-but with the writing unit in retracted position;

Fig. 3 is a sectional view taken on line 33 of Fig. 1;

Fig. 4 is a sectional view taken on line 44 of Fig. 2,

Fig. 5 is a semidiagrammatic view longitudinally through the instrument, showing a modified form;

Fig. 6 is a fragmentary view of a modified form of magnetic retracting means;

Fig. 7 is a longitudinal sectional view of a modified form of writing instrument showing the writing unit in projected postion;

' tween the writing 'unit and bore of the barrel.

Fig. 8 is a fragmentary view similar to Fig. 7, but with the writing unit in retracted position; v

Fig. 9 is a fragmentary view similar to Fig. 7, but illustrating a further modification; and

Fig. 10 is a fragmentary view illustrating the pen of Fig. 9, but with the writing unit in retracted position.

Referring in detail to the drawings, attention is directed first to Figs. 1 to 4 inclusive showing one embodiment of the invention. While the instrument illustrated is a ball point pen, it will be understood that the invention is not limited to that kind of pen, but may be embodied in writing instruments of other types, such as fountain pens. In any case, the consideration of the retractability of the writing instrument is that it may safely be inserted in a pocket in point-end-down position without a cap covering the writing point. Thus, the writing point is retracted so that the writing composition does not soil the clothes.

The writing instrument in Figs. 1 to 4 includes a barrel or casing 12 having a front section 14 and a rear section 16. The latter is also sometimes referred to merely as a cap and is connected to the front section by suitable means such as a screw threaded connection 18 for quick detachment of the barrel sections. The barrel may be made of desired suitable material, such as plastic or metal.

The writing instrument includes a writing unit 20 having a writing point 22 mounted in the barrel for sliding movement between retracted position (Fig. 2) in which the writing point is concealed within the barrel and projected position (Fig. 1) in which the writing point is exposed forwardly beyond the barrel for writing purposes. The writing unit insofar as its function is concerned in writing, may be considered a standard or conventional kind, and has a reservoir section 24 and a feed section 26 in the form of a stem leading to and mounting the ball point 22.

The barrel sections have bores 28 and 30 respectively forming a chamber 26 containing the main portion of the writing unit, and the barrel has a bore 34 at the forward end for slidingly receiving the stem 27 for guiding the unit in the projecting and retracting movements thereof. Thus, when the unit is in retracted position (Fig. 2) a portion of the stem nevertheless remains in and is guided by the bore 34. For convenience in manufacturing purposes the lower end of the reservoirsection 24 of the writing unit may be tapered as at 36.

The writing unit is retained in its projected position by means of a positive or non-yielding engagement be- The pref-erred form of means for retracting the writing unit is a magnetic means, and the unit, except for the force of the magnetic means, is free falling which facilitates movement of the unit into position for retention in projected position. Attention is directed to my "co-pending application Serial No. 490,818, filed February 28, 1955, which claims broadly magnetic means for retracting the writing unit in a retractable writing instrument.

The magnetic retraction means in the present instance takes the form of a pair of magnetic elements'38 and 40 mounted respectively in the writing unit and the rear bore portion 30. At least one of these magnetic elements is a permanent magnet and both of them may be, if desired. However, when only one is a permanent magnet it is preferred that the upper element 40 be such. The magnetic element 38 may be in the form of a plug inserted in the rear end of the reservoir section 24 of the writing unit. Means is arranged for venting-the interior of the reservoir such as by a hole through the plug or otherwise as desired. The writing unit is capable of movement in retracting direction sufiiciently to enable interengagement of the magnetic elements as in Fig. 2. In the projected position the rear end of the writing unit engages under the shoulder 42 formed in the bore 30.

This shoulder faces forwardly and is disposed to one side of the bore, extending no greater than half the circumference of the bore, so that the unit, when it is disengaged from the shoulder, is entirely free for retraction rear- Wardly beyond the shoulder into the bore 30. Preferably, the shoulder is so located that it is engaged by the rear end of the magnetic plug 38, the latter being retained laterally in position under the shoulder by resilient means 44 preferably in the form of a leaf spring secured at one end to the surface of the bore 30, While its other end is free. This spring is preferably inset in arecess 46 and arranged so that its forward free end engages the writing unit in all positions of the latter so that in the forwardmost position the spring nevertheless is in engagement with the unit and biases it laterally intc engagement with the shoulder. The spring is disposed directly opposite the shoulder.

The upper magnetic element 40, or magnet as is preferred, is mounted in the bore 30 by a suitable means such as by a press fit. Its location longitudinally of the bore is such that the writing unit is capable of retracting the unit to the position in which the plug 38 firmly en gages the magnet 40. The magnet thus retains the writing unit in retracted position in all normal positions and conditions of the pen in handling it, such as in the pocket or in a purse. To project the pen, the user merely holds it in a writing position and shakes or jars it forwardly. The magnetic influence is such that the writing unit is released by such action and the unit is moved forwardly by inertia. When it has reached its forward position so that the plug 38 is positioned for entering under the shoulder, the spring 44 moves the unit over to that side and the .unit engages the shoulder. To retract the unit, the user merely taps the rear end portion in sidewise direction on a desk. A suitable mark may be utilized for indicating the place for so tapping the pen and this may conveniently be provided by the usual pocket clip 48 which for that purpose is located on the side opposite the shoulder. When the pen is so tapped, the weight of the unit throws the rear end of the unit away from the shoulder and the attractive force of the magnet is sufiicient to retract the unit. The strength of the spring 44, relative to the weight of the unit, is so selected that the unit may be readily dislodged from the shoulder in the manner described. It is also possible to retract the pen by shaking or jarring it sharply sideways, without tapping it on a desk.

Preferably the magnetic element or plug 38 is tapered forwardly so as to present an upper extremity which is only an edge that engages the surface of the bore so as to reduce the drag of the unit in its movements.

The normal manufacturing inaccuracies provide sufficient play. between the writing unit and the forward end of the barrel to enable the rear end of the unit to be moved laterally to the desired extent for moving it into and out of engagement with the shoulder.

The shoulder 42 provides a fixed stop for retaining the writing unit rigidly, and against yielding. Suitable means may be provided for eliminating play of the unit in projecjted position. This may be accomplished at least partially by friction between the stem 27 and bore. Similarly it may be accomplished by dimensioning the taper 36 and bore 28 to have slight engagement, although the latter should not be so great as to have any retarding effeet on the retraction of the unit by the magnetic means. The attractive force of the magnetic means also aids in preventing play of the unit when the latter is in pro jected position.

The barrel sections are readily detachable as noted above by threading them apart at the connection at, 18, for removing and replacing the writing unit. No special manipulation is required in inserting the writing unit, for effecting connection between the unit and operating parts in the barrel. In order to prevent the spring 44 from clashing with the unit when the rear barrel section or cap is applied to the front barrel section when the unit is in place therein, the lower or free end of the spring may be bent outwardly a suitable extent and rounded so that in any position of the spring the inner rounded surface of the clip serves as a camming means to permit the unit to ride by the spring.

The writing instrument as constructed according to the foregoing is an unusually effective instrument. It is easily projected. This is done merely by shaking or jarring the pen as noted above. When the writing unit is projected, a rigid and non-yielding backing support is provided. It is easily and simply retracted by tapping it on a desk or table. It is virtually impossible for the writing unit to be retracted in a writing operation. It would be accidentally retracted only when it would fall on the clip side, but even if that should happen, it is easily projected again merely by shaking it.

The construction is extremely simple and rugged. It is easily and readily manipulated for replacement of the writing unit.

Figs. 1 and 2 show the rear bore portion 30 concentric with the barrel, and the writing unit, when engaged under the shoulder, as eccentric thereto. This specific arrangement is a matter of choice, however, and if it is desired to have the unit concentrically disposed when projected, an arrangement such as in Fig. 5 may be resorted to in which the rear bore 30 is eccentric to the barrel and the writing unit 20 when projecting and locked under the shoulder is concentric.

It may be desired to provide for greater attractive power of the magnetic means than as indicated above in which, for example, only one of the magnetic elements is a permanent magnet. Increased attractive power may be provided by having both of the magnetic elements permanent magnets. Another manner in which the attractive power may be increased is indicated in-Fig. 6,;where the magnetic element 59 mounted inthe writing unit 20 and the corresponding magnetic element 52 in the barrel have specially shaped interengaging surfaces 54 and 55. As shown, these surfaces are spherical and provide greatly added area of contact whereby the attraction therebetween is greatly increased. An advantage of such an arrangement may reside in a situationwhere, for example, the writing unit would tend to bounce upon hitting the upper magnetic element because of the transverse plane surfaces, but where the faces are shaped as the faces 54 or otherwise shaped to have greater area than plane surfaces and are complementary in shape to have full or complete interengagement, any such tendency to bounce is overcome and the magnetic attraction is increased.

The form of the device shown in Figs. 7 and 8 differs from that described above in thatin the present construction the pocket clip on the. instrument. is utilized in controlling the writing unit. In the present instance, the barrel 56 has a writing unit 58, thelatter being provided with a magnetic element 60 and the barrel having another magnetic element 62 thereabove, all of which are similar to the. corresponding elements in the first embodiment modified as herein below explained. When the writing unit 58 is moved to projected position, it is moved laterally into position for engaging the shoulder 64 by means of the'pocket clip 66, which extends through an opening 68 in the cap or rear barrel portion. The clip directly engages the writing unit and when it does so, it moves the upper end of the writing unit laterally as described above. The pocket clip is, of course, resilient and it functions as a spring for accomplishing the purpose stated, as well as to yieldingly grip the pocket piece when the instrument is in the pocket. The clip 66 in movingtne unit as described works against another spring 70 on the opposite side of the bore fromthe clip or on the side of the shoulder 64. This clip is preferably set in a recess 72 and it is weaker than the pocket clip so that the pocket clip will function as stated. However, the spring 70 is nevertheless capable of moving the writing unit out of engagement with the shoulder when the pocket clip is moved away from the Writing unit. This is usually done by manipulating it with the fingers, but if the user should unwittingly place the pen in his pocket without first retracting the unit, the clip in being flexed outwardly by the pocket piece is removed from the writing unit, and the spring 70 in the absence of the counteraction by the clip moves the writing unit away from the shoulder into position for retraction by the magnet 62.

The form of Figs. 9 and is essentially that of Figs. 7 and 8 with a modification providing for the clip re maining substantially entirely exteriorly of the cap and not entering through the opening therein. This is provided by an element 74 which may be generally similar to a leaf spring but essentially devoid of spring action and being quite flexible. It is mounted at one end in the inner surface of the bore of the pen, with its other and free end freely movable and extending downwardly. The element has a portion 76 positioned for engaging the unit and an outer portion 78 extending into an opening 80 in the barrel. The portion 78 terminates substantially flush with the outer surface of the barrel where it is engaged by the lower end of the spring clip 66. The clip acting through the intermediary 74 moves the upper end of the writing unit laterally to position for engaging the shoulder as described in connection with Figs. 7 and 8. However, because of the projection 78 on the element 74, the clip 66 does not enter to any appreciable extent into the opening 80 and thus remains outwardly of the cap, facilitating entry of a pocket piece between the clip and the barrel. The clip acts through the element 74 in moving the writing unit against the spring 70 and when the clip is released, the spring 70 is enabled to move the unit out of engagement with the shoulder against any incidental influence that may be exerted by the element 74. In other words, the element 74 is substantially weaker than the spring 70 if it should possess any spring action.

I claim:

1. A writing instrument comprising a casing, a writing unit slidable in the casing between a projected position and a retracted position, the casing having a forwardly facing internal shoulder disposed for engagement with the unit when the unit is in projected position, spring means continuously biasing the unit laterally towards the shoulder for engaging the unit and shoulder and releasably retaining the unit and shoulder in engagement, and permanent magnet magnetic means continuously urging the unit in retracting direction for retracting the unit upon disengagement of the unit and shoulder and for releasably retaining the unit in retracted position permitting the unit to be projected forwardly by inertia from retracted position to projected position, said magnetic means including first and second magnetic elements at least one of which is a permanent magnet, the first element being mounted in the rear end of the unit and the second element being mounted in the casing rearwardly of the first element and positioned for engagement with the first element when the unit is in retracted position.

2. The invention defined in claim 1 wherein the interengaging faces of the first and second elements are complementally shaped out of a transverse plane therebetween for increasing the area of the faces thereby increasing the attractive and holding forces of the elements.

3. The invention defined in claim 1 wherein the easing has an opening laterally therethrough, and wherein said spring means includes a pocket clip spring means on the casing having an end portion exerting pressure through said opening upon the writing unit, and wherein a secondary spring means weaker than said pocket clip spring means is disposed between the casing and said unit urging said unit out of engagement with said shoulder, said pocket clip spring means being manually releasable for enabling the secondary spring means to move the unit out of engagement with the shoulder.

4. The invention defined in claim 3 wherein said pocket clip spring means consists of a pocket clip extending through the opening directly engaging the unit.

5. The invention defined in claim 3 wherein a movable member is mounted in the casing opposite the secondary spring means and engages the unit and projects into said opening and terminates adjacent the outer surface of the casing and engages the pocket clip spring means, said movable member constituting means for transmitting force from the pocket clip spring means to the unit and for maintaining the inner surface of the pocket clip spring means adjacent the outer surface of the casing facilitating entrance of a pocket piece between the pocket spring means and the casing.

References Cited in the file of this patent UNITED STATES PATENTS 2,510,634 Hull June 6, 1950 2,584,569 Frentzel Feb. 5, 1952 2,624,315 Weisser et a1 Jan. 6, 1953 2,667,394 Goetz et a1. Jan. 26, 1954 2,676,569 Schrader Apr. 27, 1954 2,678,578 Bonanno May 18, 1954 2,688,991 Doyle Sept. 14, 1954 2,711,022 Salfelder June 11, 1955 2,734,484 OSullivan Feb. 14, 1956 2,773,478 Poinsot Dec. 11, 1956 2,776,646 Spatz Jan. 8, 1957 

